The invention generally relates to a low-voltage circuit breaker having a data memory. Preferably, the data memory is for passing characteristic values of the circuit breaker and/or of the associated current transformer to an electronic overcurrent release. Additionally, it preferably includes at least one connection line between the current transformer or transformers and the overcurrent release.
Circuit breakers are known which have a data memory which stores unchangeable characteristic values for the circuit breaker such as the type and rating current as well as characteristic values for the connected current transformer. When a release is replaced, data from the data memory is read to the release which has been inserted, and which then need not be reconfigured.
EP-B 0 493 272 discloses a circuit breaker which has an adapter board which is permanently connected to it and to which the release is connected. The adapter board includes a device for mapping the type and/or rating of the circuit breaker, as well as an output plug connector, which is connected to the release.
WO 97/08 725 discloses a further circuit breaker, whose data memory is mounted detachably on one side of the housing. This means that the data memory is also always included in the testing of the overcurrent release. If only the overcurrent release is intended to be replaced, then the data memory is disconnected from the overcurrent release and is attached to the new release, so that the characteristic values of the circuit breaker are transferred. However, during the process, there is a risk of the data memory being mislaid or confused in the course of the replacement of the release. Furthermore, the arrangement is susceptible to defects, due to the large number of plug connections in it.
In order to minimize the plug connections, it has also already been proposed for the data memory to be arranged as component of a two-part plug connection on the connection line between the current transformer and the overcurrent release, whose second component belongs to the overcurrent release. However, accommodation of the data memory in a plug part requires a specially designed component, which must be fitted with resistors individually for each switch type. The number of parameters which can be stored is, furthermore, small in this case.
An embodiment of the invention is based on the object of specifying a low-voltage circuit breaker in which the data memory operates in an improved manner, and whose construction is simple.
According to this, an electronic memory module which can be written to can be used as the data memory, and can be inserted into one of the connection lines between the current transformer or transformers and the overcurrent release.
An EEPROM, by way of example, can be used as the memory module. In order to avoid injected interference, the memory module should expediently be arranged toward the release-side end of the connection line. The memory module can include its own housing, through which the connection line runs.
On the one hand, the solution has the advantage that a sufficiently large number of parameters can be stored. The coding can be carried out in the course of testing the switch. On the other hand, normal standard plugs can be used for the plug connector. Overall, the connection line from the current transformer or the current transformers becomes a standard component in the switch manufacturing process in which the parameters of the associated switch are stored in the course of switch testing.